Hydraulic transmission clutch



May 20, 1941. I c. ca. BALCOM HYDRAULIC TRANSMIQSION CLUTCH Filed Jan. 9, 1939 ATTORNEYS Patented May 20, 1941 UNI TE D STAT-ES 'T' i- ]T G F Fl-CPE HYDRAULIC TRANSMISSION CLUTCH Clarence G. Balcom, Springdale, Conn. Application January 9, 1939;.Serial No. 250,042

1 Claim.

My inventionrelates to hydraulic =clutches. -;An, important object of my inventionis to provide a clutch that will make the coaction between the .driveand driven shafts more efiicient.

Another-,objectofzrmy invention is to provide a hydraulic clutch whereby the relation between the drive find drivenshaft may be progressively changed from a free to a locked engagement.

vYet another-object of my invention is :to provide -a.hy.draulic clutch *whereby 'the relation between .the drive and .driven shafts may be progressively changed from a vlocked to a free engagement.

.Still another object of my inventionis to provide-aihydraulic'clutch that is simple inconstruc- 'tion,--efilcient in operation and inexpensive to -ma'nufacture.

Other objects and advantages of my invention will berapparent during the course of the following description.

vIn.the-.=accompanying drawing, forming a part of this specification, and in which like numerals are employed to designatelike parts throughout thesame,

Figure 1 is a longitudinalsectional- View, showing parts inelevation, ofadeviceembodying my invention,

Figure 21s a vertical sectional view, showing parts in elevation, taken on the line 2--2iofi Fig- .vurehL-and Figure 3 .is \alvertical sectional View, taken .on the Lline.3 3 =of: Figure .1.

:In the drawing, wherein for the purpose of i1- lustration,.. is shown ,a.,preferred embodiment vof \my invention, ,the ..numeral 5, designates ,a housing havinga hub. 5 formedat one endthereot in whichjskeyed .for rotation therewith .a driven .shaft I. The housing isprovided with. acentral longitudinally extending chamber 8 having t radially disposed ,cylinderslB extending therefrom and..com1nunicating therewith. Communicating with the outer ends of the cylinders!) is an annulartpassage H] which .isseparated from the cylindersnproper by Vapartition H whichiunc- .tions asflaipartof the cylinder walls. Cylinder heads l2 arebolted, or otherwisesecured, to the housing, and effectively seal the outer, end of the cylinders.

The head. I3 is fitted into the housing 5 and formedtherein is an annular recess M of substantially the same diameter as the central chamher 8 in the housing 5, with which it is directly communicative. Concentrically arranged about the recess M are bosses l5 which are formed with a reduced outer portion l6 which fit into open- ,ings H providedin the housing. The bosses [5 {are provided with liquid receiving chambers l8 -which. are formed-with aflared lateral-passage ,l 9 incommunication with the annularrecess vIll of the housing 5. The liquid receiving chambers 18 communicate with the annular --recess l4 throughlater-al ports 20.

:Extending through the head l3 and term-inating in abutting relation with the driven shaft 1 and in longitudinal alignment therewith is a vdrive shaft 2!, having \aneccentric 22 formed ithereoncentrally of theradially disposed cylindersd. The drive-shaft =21 is provided with ball .bearings (23 and 24 to permit the free rotation 15 thereof independently of the housing! and head 13. Apac-king nut 25 iscarried byt he drive shaft, and isthreaded into the outwardly exadjacent the outer end of the stem and held against longitudinal displacement .by the transversely extending .pin.34. The packing nut 2.5 is formed with an annular projecting head 35 which is of greater diameter than theshank 2B of the head l3 and forms a seat for the adjusting disk 36 which is slidably mounted on the shank 26 and held-against outer longitudinal displacement by the head :35 of thepacking nut 25. The ad- ,iusting disk,36 is formed with an annular flange J31, theiinner face of which bears against the outer endsitll of the valves Z'L anda spring 38 is interposed between the'inner face of the flange 31 and the outer face of the head I3 to maintain theadjusting disk engaged with the head of the nut-25and touchingbutnot actuating the valves The clutch plate 36 is actuated longitudinally of the shank 26 by a clutch pedal (not shown) which is connected to the yoke lever 39 through the connecting rod 40.

Mounted to reciprocate Within the radially disposed cylinders -9 are pistons 4!, having conventional pistonrings 42 to effectively seal the cylinder walls. The underside of the pistons 4| are formed with chamfered flanges 44 which bear against the eccentric 22, and. diametrically opposed pairs of the piston ll are rigidly connected together by pins 43 which straddle the driving shaft 2| on either side of the eccentric 22, as illustrated in Figure 1.

The operation of my device is as follows:

A liquid suitable for hydraulic purposes is provided within the central passage 8 and M of the housing 5 and head I 3. It will be noted that due to the construction of the eccentric 22 one of the diametrically opposed pistons 4| will be at the outer end of the cylinder and the opposite piston thereof will be at the inner end of its respective cylinder, and that as the drive shaft is rotated the eccentric formed thereon will cause the pistons 4| to alternately reciprocate within the cylinders 9. As long as the hydraulic fluid is in the central passage 8, the drive shaft will be free to rotate independently of the housing on the bearings 23 and 24, and the pistons 4| will reciprocate freely within the respective cylinders 9. The oil will remain in the central passage as long as the clutch is depressed and holds the adjusting disk 36 in the inner position against the action of the spring 38 and with the inner face of the flange 3'! bearing against the valve stems 30 sufficient to hold the valves 21 in fully open position. As soon as the clutch is released the adjusting disk 36 will return under the action of the spring 38 to a position against the head of the packing nut 35 permitting the valves 21 to close.

Inasmuch as the valves are in no Way connected to the disk 36 they are free to operate independently of the same, and when the drive shaft 2| rotates, actuating pistons 4|, a suction will be created in the outer end of the cylinders 9. As soon as this suction is formed the valves 21 will be unseated into the flared passages I9 at each suction stroke of the piston, and the hydraulic fluid in the central chamber 8 will flow into the annular passage l through the ports 2|] of the bosses |5. The passage I0 communicates with the outer end of the cylinders, and when the piston is in the innermost position the oil will flow into the cylinder between thetop of the piston and its respective head I2.

When the piston returns on the upstroke it will be limited m the distance it can return due to the presence of the fluid between its top and piston head |2, and will therefore cause a binding action to be made between the chamfered flange 42 and the eccentric 22. As soon as this occurs, the housing 5 and head l3 will begin to revolve in accordance with the drive shaft 2|, however, as long as the space between the pistons and cylinder heads I 2 is not entirely filled there will be a certain amount of slippage between the housing and the drive shaft. Inasmuch as the driven shaft 1 is keyed to rotate with the housing, the rotation imparted to the housing will in turn be transmitted to the driven shaft I. 7

As soon as the housing begins to rotate the fluid within the passage 8 will be thrown to the outside, and because of the lateral positioning of the ports 20, will enter within the chamber N3 of the bosses I5 and as the valves 21 are opened at each suction stroke'of the piston 4|, more of the fluid will be pulled into the annular passage I8, and consequently into the space between the piston and cylinder. As soon as this space is entirely filled the driven shaft 1 will rotate in one-to-one ratio with the drive shaft 2|, and will continue to do so until the adjusting disk 36 is actuated by the clutch to open the valves 2'! and the accelerator released. The drag of the rear wheels will be transmitted to the driven shaft 1 and exert a retarding force on the housing 5 which will consequently be transmitted from the pistons 4| to the drive shaft 2|. The force exerted will cause the pistons 4| to reciprocate slightly within the cylinders 9. When the valves 21 are held open, a clear passage leads from the annular passage H] to the inner chamber 8, and the reciprocation of the pistons 4| will force the fluid out of the space between the piston and cylinder head and into the said central chamber. This will take but a very short time after the valves 21 have been opened. As soon as the space between the piston and cylinder head has been cleared of the fluid, the piston will be free to reciprocate Within the cylinders and no rotary motion will be transmitted to the housing or to the driven shaft 1.

It may be seen that by varying the amount of fluid between the piston and cylinder head progressively from a full to an empty condition, the ratio of the driven shaft 1 to the drive shaft 2| may be progressively altered. When the said space is empty there will be no motion transmitted to the housing 5 or the driven shaft 1, and as increasingly greater amounts of fluid are introduced into this space the slippage of the drive shaft with the housing will become increasingly less, and as soon as the fluid entirely fills the space no slippage at all will be evident between the drive shaft and the housing, and the ratio ,of the drive shaft to the driven shaft will be one-to-one.

It is to be understood that the form of my invention herewith shown and described is to be taken as a preferred example of the same, and that various changes in the size, shape and arrangement of parts may be resorted to without departing from the spirit of my invention, or the scope of the appended claim.

Having thus described my invention, I claim:

In a hydraulic clutch of the type including a casing having a fluid chamber and cylinders opening into the chamber, pistons operating within the cylinders and passages connecting the fluid chamber with the outer ends of the cylinders, the improvement comprising valves positioned within the passages and having valve stems extending exteriorly of the casing, said valves unseating in the direction of the pistons and controlling the flow of fluid through the passages, spring means urging the valves in a direction to close the passages, suction existent in the outer ends of the cylinders during the suction stroke of the pistons unseating the valves against the resilient action of the spring means and drawing fluid from the chamber into the outer ends of the cylinders, and a manually operated actuator plate movable into engagement with the valve stems to simultaneously unseat all of said valves and to hold the valves in the said unseated position, whereby operation of the vpistons will discharge the fluid in the cylinders into the central chamber.

- CLARENCE G, BALCOM. 

